Abstract: The present invention relates to an apparatus for automatically locking and unlocking a vehicle seat belt, which automatically locks and unlocks seat belts of a driver seat and a passenger seat of a vehicle. The apparatus includes: a first housing 10; a second housing 20; a belt-locking bar 40 having one end coupled to a hinge portion 30 provided at the center of a connection portion between the first and second housings 10 and 20; a movable block 61; a retractor 50; a chest protecting belt 60 having one end connected to the movable block 61; an abdomen protecting belt 70; and a controller 100 for controlling the rotation of the belt-locking bar 40. According to the present invention, the seat belt is automatically locked at the time of a start of a vehicle engine without being manually worn by a driver or a passenger getting in the vehicle.